To date, several solutions have been proposed for managing logical forwarding elements in virtualized computing environments. Some of these solutions use a cluster of controllers to manage the logical network elements. For some of these functionalities, these logical forwarding elements are implemented by physical forwarding elements (e.g., software or hardware switches) that are configured and managed by the controller cluster.
Some of the operations of these managed physical forwarding elements need data from the controllers to process packets or messages. These communications are typically out-of-band, control channel communications. Often, due to the large number of host computers that execute software forwarding elements, the controllers have control channel connections with a large number of host computers. Such large number of connections can tax the resources of any one controller, especially when the load is unevenly distributed between the controllers. Accordingly, there is a need for a novel scheme for distributing the control channel load on the controllers of a multi-controller network control system.